Pneumatic tool



Nov, 26, 1929. A. HAriss EN rnmumnc Toop Filed Dec. 18. 1922 2-Sheets-Sheet 1 Zz/En/Z f//zssen wy Nov. 26, 1929. A. HA-NSSEN PNEUMATICT001,

Filed Dec. 18. 1922 2 Sheets-Sheet 2 Patented Nov. 26, 1929 castes IVERA. HANSSEN, OF AURORA, ILLINOIS, ASSIGNOB TO INDEPENDENT ENEU'MATIG TOOLCOMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF DELAWARE methane i ooriAppneefieh fiIed'fieeeiiiber 1a, 1922. Serial N6. Ger/ass.

This invention relates to piston actuated pneumatic or other fluidoperated tools of the portable type, and has-particular reference to thecountenWeightihg of the crank (shaft at both ends to properly balancethe shaft and secure a perfectly running tool.

movable so that the shaft, before the said counter-weight is applied,may be inserted through the bearing sleeves and "eccentric straps of therods connecting the pistons and valves with said shaft in assembling thetool and thus employ solid or one-piece sleeves and straps for thepistons and valves, respectively. v

Another object of the invention is toprovide at the removablecounter-weight a tension plate for holding the crank shaft againstendwise movement.

A further object of my invention is" to provide improvements in theone-piece bearing sleeves for the connecting rods and to also provide anovel means of releasably connecting the valves with their eccentricstraps.

The invention consists further in the matters hereinafter described andmore particularly set forth in the appended claims.

In the accompanying drawings Fig. 1 is a longitudinal sectional viewthrough the central portion of a pneumatic drill embodying the featuresof my invention;

Fig. 2 is a transverse vertical sectional view taken on line 2-2 of Fig.1;

Fig. 3 is a transverse vertical sectional view taken on line 33 of Fig.1;

Fig. 4 is a like view showing the removable counter-weight removablyconnected with the crank shaft in a manner difi'erent from thatindicated in Fig. 3;

Figs. 5 and 6 are transverse sectional viewstaken on lines 55 and 6-6respectively, of Fig. 1;

Fig. 7 is a longitudinal sectional View taken on line 77 of Fig. 5; r

Fig. 8 is a view of the split ring for holding the eccentric straps onthe crank shaft;

Fig. 9.is a view of one of the split rings for the bearing sleeves ofthe connecting rods; g Y weight both ends of the crank shaft 3. This and. Fig. '10 is a view showing a; bearing sleeve cf connecting rodwithsplit retaining ring removed. p I V r The drill shown in F i 1 hasan ontside casing divided into connected sections 1 and 2, :The main orrearmost section 1 contains t crank shaft 3', and the forward section 2tne'drill spindle 4-. These'two parts, in the particularstructure shownin Fig. 1,. are in alignment and are geared together so that power maybe transmitted from the crank shaft 8 to the spindle 4:. The lattercarries the usual tool holding chuck (not shown) at its forward end, andthe section 1 carries on the outside cylinder blocks 5, 5 arranged at anangle and on opposite sides of the crank shaft 3.

Each cylinder block 5 is provided with two power cylinders 6, 6 and aninterposed valve cylinder 7. In each power cylinder is ja piston Sand111' each valve cylinder 7 1s a recipro'cating valve member 9. Eachpiston 8' and valve member 9 are connected vvith the crank shaft 3 in amanner to be presently described.

"The valve members 9, 9 control the supply and exhaust of motive fluidto and from the power cylinders 6, 6', there being a suitablearrangement of ports and passages for this purpose. As these do not formpart of my present invention, there is noiie'ed to describe them. .Thepower and valve cylinders 6, 7 are lined with removable wear resistingbushings 10, 11, held in place by head plates 12, 12 secured to thecylinder blocks, as shown. This construction forms the subject-matter ofthe copending application of Reinhold A. Norling, filed December 18,1922, Serial'No. 607,619, now Patent No. 1,529,911. I

The crank shaft 3 has its forward end, that is, its end adjacent thedrill spindle, supported by an antifriction bearing 13 in the forwardend of the casing'l. The opposite end of the shaft 3 is supported by anantifri'ction bearing 14 in the block 15 of the tool handle 16. Thelatter is secured by bolts 17 to the rear end of the casing 1 andcontains the usual valve controlled supply passage for the motive fluidfor the tool.

Qne object of my invention is to counter- 7 weight 19 is provided with anumber of flat faces 20 arranged part way around the shaft to make thatportion of the same partly hexagonal in cross-section, as illustrated inFig.

' 3. The remaining portion of the shaft is not r of the faces 20 and 21is slightly enlarged milled'but left round or circular, as at 21, toprevent the counter-Weight 19 from being put on the wrong way. The boreof the counterweight willhave a shape complementary to that of the shaftpart on which it fits.v The portion ofthe shaft 3 immediately forward toprovide an annular stop shoulder 22. The other side of the shaft'isreduced so that the counter-weight 19 may be slipped over the 7 samewhen inserting it in place or removing it from the shaft upondismantling the tool.

- To hold, the counter-weight 19 againstthe shoulder 22, the inner ringv23 of the hearing 14 fits against the same, as shown in Fig. 1. Awasher 24 is held against the opposite 7 side of this ring 19 by a clampnut 25 on the threaded end of the shaft 3, as shown in Fig.

' 1. The outer ring 26 of said bearing 14 seats in an annular recess 27in the block 15 of the i handle 16, and said ring is held in said recessby a spring steel disc 28. 7

The disc 28 is normally fiat; that is, when notin place in the toolcasing, it has all portionsfin the same plane. The disc 28 is clamped inplace between the overlapping parts of the handle block 15 and thecasing 1, as shown in Fig. 1. The inner or central portion of the disc28 overlaps the outer ring 26 to hold it in place. The casing 1 andhandle part 15 being clamped together by the bolts 17 and the innerportion of the disc 28 resting against the bearing ring 26, causes thedisc to be flexed into the shape shown in Fig. 1 when the parts areclamped together, and that flexing maintains the disc 28 against thebearing ring 26 and effectively holds it in place. By the structuredescribed, the crank shaft 3 is held against endwlse movement inboth'directions, in onedirection by the handle block 15, and in theopposite direction by the disc28.

The pistons 8, 8 1n the power cylinders 6, 6 are connected with thecrank shaft 3 by connecting rods 29, 29. Each connecting rod 29 is madein two main parts,'one part being a continuous, one piece bearing sleeve36 surrounding the shaft 3, at the place provided the associated sleeve.

therefor, and the other part being a pitman or rod 31 having a ball andsocket connection at one end with the associated piston 8 and r areleasable connection at the other end with its bearing sleeve 30. Thisconnection, as shown in Fig. 6 of the drawings, consists of a radial lug32 on the bearing sleeve to re ceive the inner end of the rod 31. Therod is screwed into the lug and the latter is split so that a clampscrew 33 may be used for holding the rod in place and against turning,as in Patent No. 1,391,847, granted September 27, 1921, toReinhold A.Nor-ling.

Anti-friction bearing balls 34 are interposed between each bearingsleeve 30 and the associated crank pin portion of the shaft 3. For theseballs the shaft 3 and bearing sleeve 30 are grooved to providerace-ways'35, 35'. For each sleeve 30, I provide a split retaining ring36. This fits in the sleeve 30 on one side of the balls 34 and holdsthem in place. The opposite side of the race-way 35 in the sleeve. 30is'formed toresist movement of the balls in that direction, as shown inFig. 1.

In addition to the groove 35, the sleeve 30 has an internal annulargroove 37 to receive the retaining ring 36. This groove opens outwardthrough "the sleeve 30. at one side through a gap or passage 38 (Fig.10), and this accommodates the severed lugs 39. (Fig. 9) at the splitendof the retaining ring 36, as shown in Fig. 6.v The opposed sides of thegap 38 are grooved, as at 40, 40, to receive these lugs 39. The latterproject radially outward beyond the sleeve 30 to be reached forcontracting the ring 36 and removing it from This allows the sleeve 30to be slipped over the inner end of the crank shaft 3 when the removablecounterweight 19 is oif. The balls 34 areinserted into the race-way 35through the gap 38 and held in place after the retaining ring 36 isinserted in place.- I

As shown in Fig. 1, the eccentric 41 of the crank shaft 3 is locatedbetween the two sets the strap 42 from displacement in that direction.At the other side of said strap there is a split retaining ring 44. Thisfits in a groove 45' in the crank shaft 3, and when in place holds thestraps 42 on the eccentric 41.

Each valve member 9 has an inwardly projecting stem 46 (Fig. '7) andthis carries a cross-pin 47. Each strap 42 has an outwardly projectingradial lug 48 overlapping thestem 46 of the associated valve 9 andprovided with a hole to receive the pin 47, as shown in Figs.

5 and 7 This provides a releasable connection between the valves andstraps 42.

The inner end of the casing 1 is open when the handle 16 is removed andallows the counter-weight 19 to be inserted therein when assembling thetool. The bearing sleeves and straps 42 for the pistons 8 and valves 9on opposite sides of the shaft 3 are arranged in pairs, as shown inFig. 1. The parts of each pair have sideways engagement as shown. Thecylinders 6 on one side of the crank shaft 3 have the longitudinalcenters of their bores in line with the centers of the associatedsleeves or rings 30. The cylinders 6 on the other side are offset to bein the same relation to their sleeves 30. The lugs 32 of said sleeves 30are central with respect to their sleeves 30.

Providing the crank shaft 3 with two counter-weights 18 and 19, arrangedon opposite sides of the power pistons and adjacent the connecting rodsof the same, balances the shaft and insures a perfectly running tool,

because the counter-weight 18 balances the connecting rods 29 next toit, and the counfer-weight 19 does the same for the connecting rods 29next to the same. This balances the crank shaft against the powerstrokes of the pistons in the power cylinders and secures a properlyrunning balance for the tool. The counter-weight 19 at the inner end ofthe shaft 3 having removable connection therewith permits the use ofone-piece sleeves 3 and straps 42 for the pistons and valves,respectively. With one-piece sleeves and straps, split parts and clampbolts therefor are avoided. This makes the structure a jar proof one andone that is strong and compact by avoiding the use of joined parts andprojecting bolts and lugs as heretofore.

In Fig. 4, I have shown a counter-weight 19 releasably connected withthe shaft 3 in a manner different from that in Figs. 1 t0 3. As shown inFig. 4, the shaft 3 is circular in cross-section at the counter-weight19 and fits in the like shaped bore thereof. A key 19 is used as theconnection between the shaft and counter-weight 19 afhile T have shownand described herein in detail a structure of my invention, it is ofcourse to be understood that the details of construction and arrangementof parts may be variously changed and modified without departing fromthe spirit and scope of my invention.

I claim as my invention:

1. In a portable piston actuated pneumatic too-l having a casing, ahandle closing the rear end of the casing and removably secured thereto,a one-piece crank shaft in said casing for actuating the pistons of thetool with the forward and rear ends of said shaft journaled in thecasing and handle, respectively, two counter-weights on said shaft, oneadjacent each end thereof, said shaft adjacent its rear end having ashoulder and flat and curved surfaces adjacent the same, the rearcounter-weight having its bore shaped to be held on the shaft by saidfiat surfaces, and means carried by said handle and engaging said weightfor holding the same against said shoulder. I

2. In a portable piston actuated pneumatic tool having a casing, thecombination with a handle closing the inner end of the casing andremovably secured thereto, of a one-piece crank shaft in the casing foractuating the pistons of the tool with the forward and rear ends of theshaft journaled in the casing and handle, respectively, twocounter-weights on said shaft, one adjacent each end thereof, the rearcounter-weight having removable connection with said shaft,- the journalfor the rear end of the shaft being an antifriction bearing havinginnerand outer bearing rings with bearing balls therebetween, the outerring seating in a recess in the handle to prevent endwise movement ofthe shaft in one direction, and a steel disc clamped in position betweenthe handle and casing and engaging the outer ring for holding the shaftagainst endwise movement in the opposite direction. In a portable pistonactuated pneumatlc tool having a casing, the combination with a handleclosing the inner end of the casing and removably secured thereto, of aone-piece crank shaft in the casing for actuating the pistons of thetool with the forward and rear ends of the shaft journaled in the casingand handle, respectively, two counter-weights on said shaft, oneadjacent each end thereof, the rear counter-weight being removablymounted on said shaft, said shaft having a shoulder in front of saidrear counter-weight, the journal for the inner end of the shaft havinginner and outer rings with bearing balls therebetween, the outer ringseating in the recess in said handle, and a steel disc clamped betweenthe hindle and casing and having its inner portion extending over andengaging the outer ringon the outside thereof, said disc having itscentral portion flexed out of the plane of its outer edge when clampedbetween said handle and easing.

In testimony that I claim the foregoing as my invention, T afliX'mysignature this 12th day of Dec, A. D. 1922.

IVER A. HANSSEN.

